1864 BEACHSIDE CT GAF Energy Structural Letter_Timberline ES Solar_Dalton_S_S_12.19.23_1
December 19, 2023
Jared Vaught
GAF Energy
125 Mitchell Blvd, #D
San Rafael, CA 94903
Re: Engineering Review
Dalton Residence
1864 Beachside Court
Atlantic Beach, FL 32233
10 kW Grid Tied Solar System
Wind Load Data at Residence:
Risk Category II / Exposure Category B / Wind Speed: 129mph
Dear Mr. Vaught:
Please allow the information below to serve as the load analysis associated with 1603.1.8.1 of the 2020
Florida Building Code. From the below information and calculations, removing standard shingles and
replacing with Timberline Solar ES system reduces the load on the existing structure.
Loads:
Based on the information provided, the Timberline Solar ES product weights 10 lbs. per energy shingle.
The shingle size is 17.125 in X 63.8 in. The weight of the product is therefore, 1.32 lbs/sq ft (psf).
Provided that most residential roofs have a typical asphalt comp shingle roof with weight ranges
between 2 psf and 4 psf per layer. Timberline Solar ES specification sheets have been provided to the
AHJ within the permit plan set.
Sample Calculation:
Existing Condition New Condition
Roofing (Asphalt Comp Shingle) 1 Layer: 2.5 psf Timberline Solar ES: 1.32 psf
Underlayment: 0.5 psf Underlayment: 0.5 psf
Sheathing: 1.5 psf Sheathing: 1.5 psf
Framing (2x4 @ 24” O.C. assumed) 1.0 psf Framing (2x4 @ 24” O.C. assumed) 1.0 psf
Miscellaneous: 1.5 psf Miscellaneous: 1.5 psf
Total Roof Dead Load: 7.0 psf Total Roof Dead Load: 5.82 psf
Sincerely,
Cory Glass, P.E.
FL License No. 80467